The invention concerns testing methods for evaluating the function of an absorbent sanitary product, in particular a diaper, incontinence pad or incontinence briefs, sanitary towel or the like, wherein the sanitary product is to be examined e.g. in view of liquid absorption, liquid distribution, rewetting behavior or residual moisture. This is achieved, in particular, by a method for determining the moisture subsequent to prior application of liquid onto the sanitary product, advantageously under predetermined conditions.
There are numerous conventional testing and measuring methods for determining and evaluating the absorption characteristic of absorbent sanitary products of the type at issue. For example, EP 0 887 055 A1 describes a standardized process for wetting a sanitary product using a dummy having the shape of a human body, wherein the diaper is provided with a moisture sensor that is observed.
This document also discloses a standardized wetting process of a sanitary product in a spread-out planar state to be performed in a laboratory. It also describes a test for determining the rewetting behavior, wherein sections of a collage film material are applied with pressure onto the previously wetted location, and the liquid or moisture absorption thereof is determined.
The testing method UNE 153601-2 of the Spanish standards organization AENOR describes a similar test. This testing method also includes applying liquid to the center of the product length of a spread-out planar sanitary product and determining rewetting into a filter paper that has been applied and pressed onto the sanitary product.
The medical service of Germany (Medizinische Dienst Deutschland) also provides a testing method in part 3 of the test specifications 1/93 MDS-HI, which also determines rewetting after introduction of liquid under load and determines rewetting using filter paper. In this method, however, samples are initially taken from several representative points of an incontinence product, to which synthetic urine is applied and which are then measured. This method is not performed in a non-destructive fashion and is therefore remote from practice.
A similar method is described in the Italian testing method NMC 93 part numbers 1 to 3 for testing the absorption capacity, absorption speed and retention power of incontinence products. In this connection, samples of a size of 100×100 mm are removed from a front, center and rear area of an incontinence product. The removed samples are wetted and then disposed onto a draining lattice and loaded in a predetermined fashion. Rewetting is subsequently determined as the difference between the dry and the we sample.
The test has little relevance for actually occurring wear situations of the intact sanitary product due to destruction of the absorbent area of the sanitary product and complete wetting of the samples.
In the conventional methods, each parameter to be measured is determined in unrealistic test situations, which substantially differ from wear situations that actually occur during use of a sanitary product. The results of the conventional test methods therefore do not give any reliable conclusions about the function of a sanitary product during actual use. This was realized with the present invention.
It is the object of the present invention to provide a method of the above-mentioned type and as described in the independent claim, which permits realistic conclusions regarding the operational behavior and, in particular, liquid absorption characteristics, liquid distribution characteristics or rewetting characteristics of a sanitary product.